1/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
2/*
3 * Copyright (c) 2007 Cisco Systems.  All rights reserved.
4 * Copyright (c) 2020 Intel Corporation.  All rights reserved.
5 */
6
7#ifndef IB_UMEM_H
8#define IB_UMEM_H
9
10#include <linux/list.h>
11#include <linux/scatterlist.h>
12#include <linux/workqueue.h>
13#include <rdma/ib_verbs.h>
14
15struct ib_ucontext;
16struct ib_umem_odp;
17struct dma_buf_attach_ops;
18
19struct ib_umem {
20	struct ib_device       *ibdev;
21	struct mm_struct       *owning_mm;
22	u64 iova;
23	size_t			length;
24	unsigned long		address;
25	u32 writable : 1;
26	u32 is_odp : 1;
27	u32 is_dmabuf : 1;
28	struct sg_append_table sgt_append;
29};
30
31struct ib_umem_dmabuf {
32	struct ib_umem umem;
33	struct dma_buf_attachment *attach;
34	struct sg_table *sgt;
35	struct scatterlist *first_sg;
36	struct scatterlist *last_sg;
37	unsigned long first_sg_offset;
38	unsigned long last_sg_trim;
39	void *private;
40	u8 pinned : 1;
41};
42
43static inline struct ib_umem_dmabuf *to_ib_umem_dmabuf(struct ib_umem *umem)
44{
45	return container_of(umem, struct ib_umem_dmabuf, umem);
46}
47
48/* Returns the offset of the umem start relative to the first page. */
49static inline int ib_umem_offset(struct ib_umem *umem)
50{
51	return umem->address & ~PAGE_MASK;
52}
53
54static inline unsigned long ib_umem_dma_offset(struct ib_umem *umem,
55					       unsigned long pgsz)
56{
57	return (sg_dma_address(umem->sgt_append.sgt.sgl) + ib_umem_offset(umem)) &
58	       (pgsz - 1);
59}
60
61static inline size_t ib_umem_num_dma_blocks(struct ib_umem *umem,
62					    unsigned long pgsz)
63{
64	return (size_t)((ALIGN(umem->iova + umem->length, pgsz) -
65			 ALIGN_DOWN(umem->iova, pgsz))) /
66	       pgsz;
67}
68
69static inline size_t ib_umem_num_pages(struct ib_umem *umem)
70{
71	return ib_umem_num_dma_blocks(umem, PAGE_SIZE);
72}
73
74static inline void __rdma_umem_block_iter_start(struct ib_block_iter *biter,
75						struct ib_umem *umem,
76						unsigned long pgsz)
77{
78	__rdma_block_iter_start(biter, umem->sgt_append.sgt.sgl,
79				umem->sgt_append.sgt.nents, pgsz);
80	biter->__sg_advance = ib_umem_offset(umem) & ~(pgsz - 1);
81	biter->__sg_numblocks = ib_umem_num_dma_blocks(umem, pgsz);
82}
83
84static inline bool __rdma_umem_block_iter_next(struct ib_block_iter *biter)
85{
86	return __rdma_block_iter_next(biter) && biter->__sg_numblocks--;
87}
88
89/**
90 * rdma_umem_for_each_dma_block - iterate over contiguous DMA blocks of the umem
91 * @umem: umem to iterate over
92 * @pgsz: Page size to split the list into
93 *
94 * pgsz must be <= PAGE_SIZE or computed by ib_umem_find_best_pgsz(). The
95 * returned DMA blocks will be aligned to pgsz and span the range:
96 * ALIGN_DOWN(umem->address, pgsz) to ALIGN(umem->address + umem->length, pgsz)
97 *
98 * Performs exactly ib_umem_num_dma_blocks() iterations.
99 */
100#define rdma_umem_for_each_dma_block(umem, biter, pgsz)                        \
101	for (__rdma_umem_block_iter_start(biter, umem, pgsz);                  \
102	     __rdma_umem_block_iter_next(biter);)
103
104#ifdef CONFIG_INFINIBAND_USER_MEM
105
106struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
107			    size_t size, int access);
108void ib_umem_release(struct ib_umem *umem);
109int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
110		      size_t length);
111unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
112				     unsigned long pgsz_bitmap,
113				     unsigned long virt);
114
115/**
116 * ib_umem_find_best_pgoff - Find best HW page size
117 *
118 * @umem: umem struct
119 * @pgsz_bitmap bitmap of HW supported page sizes
120 * @pgoff_bitmask: Mask of bits that can be represented with an offset
121 *
122 * This is very similar to ib_umem_find_best_pgsz() except instead of accepting
123 * an IOVA it accepts a bitmask specifying what address bits can be represented
124 * with a page offset.
125 *
126 * For instance if the HW has multiple page sizes, requires 64 byte alignemnt,
127 * and can support aligned offsets up to 4032 then pgoff_bitmask would be
128 * "111111000000".
129 *
130 * If the pgoff_bitmask requires either alignment in the low bit or an
131 * unavailable page size for the high bits, this function returns 0.
132 */
133static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
134						    unsigned long pgsz_bitmap,
135						    u64 pgoff_bitmask)
136{
137	struct scatterlist *sg = umem->sgt_append.sgt.sgl;
138	dma_addr_t dma_addr;
139
140	dma_addr = sg_dma_address(sg) + (umem->address & ~PAGE_MASK);
141	return ib_umem_find_best_pgsz(umem, pgsz_bitmap,
142				      dma_addr & pgoff_bitmask);
143}
144
145struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
146					  unsigned long offset, size_t size,
147					  int fd, int access,
148					  const struct dma_buf_attach_ops *ops);
149struct ib_umem_dmabuf *ib_umem_dmabuf_get_pinned(struct ib_device *device,
150						 unsigned long offset,
151						 size_t size, int fd,
152						 int access);
153int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf);
154void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf);
155void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf);
156
157#else /* CONFIG_INFINIBAND_USER_MEM */
158
159#include <linux/err.h>
160
161static inline struct ib_umem *ib_umem_get(struct ib_device *device,
162					  unsigned long addr, size_t size,
163					  int access)
164{
165	return ERR_PTR(-EOPNOTSUPP);
166}
167static inline void ib_umem_release(struct ib_umem *umem) { }
168static inline int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
169		      		    size_t length) {
170	return -EOPNOTSUPP;
171}
172static inline unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
173						   unsigned long pgsz_bitmap,
174						   unsigned long virt)
175{
176	return 0;
177}
178static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
179						    unsigned long pgsz_bitmap,
180						    u64 pgoff_bitmask)
181{
182	return 0;
183}
184static inline
185struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
186					  unsigned long offset,
187					  size_t size, int fd,
188					  int access,
189					  struct dma_buf_attach_ops *ops)
190{
191	return ERR_PTR(-EOPNOTSUPP);
192}
193static inline struct ib_umem_dmabuf *
194ib_umem_dmabuf_get_pinned(struct ib_device *device, unsigned long offset,
195			  size_t size, int fd, int access)
196{
197	return ERR_PTR(-EOPNOTSUPP);
198}
199static inline int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf)
200{
201	return -EOPNOTSUPP;
202}
203static inline void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf) { }
204static inline void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf) { }
205
206#endif /* CONFIG_INFINIBAND_USER_MEM */
207#endif /* IB_UMEM_H */
208